Electro-chromic materials (EC) are a new class of electronically reconfigurable thin films that have the ability to reversibly change optical properties by electric charge insertion/extraction. Since their discovery by Deb, they have been employed in applications related to display technology, such as smart windows and mirrors and active optical filters. In this sense, a variety of studies related to the tuneable optical characteristics of EC materials have recently been reported, however, their microwave tuneable dielectric characteristics have been left somewhat unexplored. In 2016 Bulja, showed that dc bias voltage induced modulation of the optical characteristics of an inorganic Conductor/WO3/LiNbO¬3/NiO/Conductor EC cell is accompanied by the modulation of its high frequency (1-20 GHz) dielectric characteristics. In principle, to produce tailor-made dielectric characteristics, EC cells of different material compositions are needed. Here, we report the discovery that the microwave dielectric and the optical characteristics of an EC cell can be engineered to suit a variety of applications without changing their material composition. The obtained results indicate the potential for producing novel, tuneable and tailor-engineered materials that can be used to create next generation agile microwave-optical devices.